Plate Tectonics

Plate tectonics

The study of the formation and movement of Earth’s crustal plates

Inner core

The center of the Earth. Made of solid iron and nickel.

Outer core

Liquid iron, gives earth its magnetic field

Mantle

The largest portion of the earth, made of dense rock.

Asthenosphere

The upper most region of the mantle.

Oceanic crust

3-6 miles thick, very dense

Continental Crust

20-50 miles thick, less dense

Crust

The “outer skin” of the earth

Continental drift

Continents once formed a single land mass called Pangaea, and drifted apart.

Alfred Wegener

1912 geologist proposed the theory of continental drift.

Pangaea

Land mass of all the continents.

Evidence for plate tectonics

The continents look like they “fit together”Fossils of the same type and age found on different continents

Matching rock types

Earthquake and volcano locations

Mid-ocean ridges and trenches

Diverging Boundary

sliding boundary

Sun-ducting boundary

Collision Boundary

Hot Spot: Hawaii diagram

Accreted Terrance

A chunk of land from another location

Micro Plate

Rocky Mountain Formation

A shallow angle sub-ducting oceanic plate which pushed up the overlying continental crust.

Hot-spot

A stationary plume of magma in the mantle which will create a chain of islands as they slide over.

Shield volcano

Lava is runny, Hawaiian islands

What happened to molokai

A giant land slide. Debris is scattered northward in the bottom of the pacific ocean.

Why are the hawaiian islands getting smaller

sinking

erosion

Isostacy

A balance of gravitational forces pushing up and down on the Earths crust

Isostacy related to plate tectonics

High mountains have roots underneath them so they can float.

Layers of the earth

Inner core, outer core, mesosphere, crust